System and Method for Generating Flame Effects

ABSTRACT

A system and method for generating flame effects. The system includes an array of burner heads, each having an igniter configured to generate an ignition spark. The system also includes a reservoir of a high flash point liquid and a pump configured to draw the high flash point liquid from the reservoir and pump it to the array of burner heads under high pressure. A valve is arranged at each burner in the array of burner heads to control a flow of the high flash point liquid through each burner head. Also, a nozzle is arranged at each burner head to atomize the high flash point liquid before ignition. A sensor is arranged at each burner head to generate an ignition confirmation signal upon detecting the ignition spark at the igniter. Accordingly, a controller is configured to independently control each valve to restrict the flow of the high flash point liquid to the burner unless the ignition confirmation signal is received from the sensor monitoring the burner.

CROSS-REFERENCE TO RELATED APPLICATION

Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

BACKGROUND OF THE INVENTION

The present invention relates generally to a system and method for generating flame effects and, more specifically, to a system and method for generating flame effects using a pumping system having a plurality of valve points configured to feed a material that is combustible when atomized or vaporized to an array of independently controllable burners.

Effects systems are commonly used in a variety of entertainment environments. For example, some effects systems are individually designed for the filming of feature films and television programs while other systems are found in stage shows and at amusement parks that seek to repeatedly generate a realistic recreation of specific events.

One common effect utilized in both types of effects systems is a flame effect that is typically generated by ejecting and igniting a volatile and combustible liquid or gas along a desired path. For example, U.S. Pat. No. 5,756,920, which is commonly assigned to Sigma Services, Inc., discloses a system that pressurizes propane into a liquid state and, using a regulator, permits a portion of the propane to escape through a nozzle where it encounters a pilot flame and is ignited to generate a mushroom-shaped flame. In this regard, the resulting flame yields the appearance of an explosion and is often used in action scene simulations commonly found at amusement parks and various stage shows.

However, while these systems provide a highly accurate simulation of explosive flames, additional features are desired in some settings that are difficult and/or costly to achieve with these systems. For example, these systems are generally limited in the number of recursive firings that are possible. That is, since the systems rely on a pressurized flammable gas and a regulator that controls the escape of the gas from a pressurized vessel, recursive firing is limited by the sustainability of pressurization and the supply of flammable gas contained in the pressurized vessel. Once the supply of flammable gas contained in the pressurized vessel is consumed, the pressurized vessel must be physically disconnected from the system and replaced with a new vessel filled with the flammable gas or the pressurized vessel must be otherwise refilled. In either case, this can be a fairly arduous and time-consuming process that can significantly limit the applications in which the system can be utilized. Similarly, by using a pressurized material and a regulator, the system may be negatively impacted by changes in the surrounding weather conditions, such as temperature and pressure changes.

Additionally, should a single pressurized reservoir of flammable gas be utilized to supply an array of nozzles, it may be difficult to accurately control each nozzle independently, such that the nozzles fire in a successive or highly sequenced pattern. That is, though a single, localized pressure vessel serving as a reservoir of flammable gas is desirable for logistic considerations, the single pressure source has a discrete amount of pressure that can be utilized over a given firing interval before it is significantly diminished and must be reloaded and/or re-pressurized. Therefore, even if flow from a given nozzle in the array is limited over a particular time while other nozzles in the array fire, when that nozzle is permitted to fire, the supply of pressurized flammable gas may be exhausted or significantly diminished, making the system unable to generate the flame effect desired from the nozzle.

Therefore, it would be desirable to have a system and method for generating a flame effect that is highly controllable over multiple successive firings. In particular, it would be desirable to have a modular flame effect and control system that allows highly accurate isolation and control of individual portions of a flame effect system to generate a sustainable pattern of firings mapped to a desired sequence.

BRIEF SUMMARY OF THE INVENTION

The present invention overcomes the aforementioned drawbacks by providing a system and method for generating flame effects using a pumping system having a plurality of valve points configured to feed a material that is combustible when atomized or vaporized to an array of independently controllable burners. Both the pump and the valve points can be controlled to generate a sustainable pattern of firings mapped to a desired sequence.

In accordance with one aspect of the invention, a system generating flame effects is disclosed. The system includes an array of burner heads, each having a burner configured to generate an ignition spark. The system also includes a reservoir of a high flash point liquid and a pump configured to draw the high flash point liquid from the reservoir and pump it to the array of burner heads under pressure. A valve is arranged at each burner in the array of burner heads to control a flow of the high flash point liquid through each burner head. Also, a nozzle is arranged at each burner head to atomize the high flash point liquid to a combustible form. A sensor is arranged at each burner head to generate an ignition confirmation signal upon detecting the ignition spark at the igniter. Accordingly, an ignition module is configured to independently control each valve to restrict the flow of the high flash point liquid to the igniter unless the ignition confirmation signal is received from the sensor monitoring the burner.

In accordance with another aspect of the invention, a system for generating flame effects is disclosed that includes a reservoir having a material stored therein that is in a liquid state and combustible when atomized or in a gaseous state. A pump is included that is configured to move the material from the reservoir toward an expelling port where at least one burner head is disposed. Each burner head includes a nozzle configured to receive the material and atomize or vaporize the material, and a valve configured to restrict the material from passing from the nozzle. Each burner head also includes a sparking igniter configured to ignite the material as it passes from the nozzle to generate the flame effects, and a sensor configured to monitor the igniter to determine ignition of the burner. An ignition module is included that is configured to control power supplied to the valve to restrict the material from passing from the nozzle if the sensor has not determined ignition of the igniter.

In accordance with yet another aspect of the invention, a method for generating flame effects is disclosed that includes pumping a high flash point liquid from a reservoir toward a plurality of nozzles configured to atomize the high flash point liquid to a combustible form. The method also includes igniting a burner associated with each of the plurality of nozzles according to a predetermined pattern to ignite the combustible form of the high flash point liquid and generate the flame effects. As such, the method includes monitoring each burner to confirm ignition of each burner according to the predetermined pattern and independently controlling valves associated with each of the plurality of nozzles to only open a valve after ignition of the burner has been confirmed.

Various other features of the present invention will be made apparent from the following detailed description and the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference is hereby made to the following drawings in which like reference numerals correspond to like elements throughout, and in which:

FIG. 1 is a schematic diagram of a pumping system in accordance with the present invention; and

FIG. 2 is a schematic diagram of a burner system in accordance with the present invention that is designed to receive a material for combustion from the pumping system of FIG. 1.

DETAILED DESCRIPTION

Referring to FIG. 1, a schematic diagram of a pumping system 10 in accordance with the present invention as shown. Pumping system 10 includes a high pressure pump 12 that draws a high flash point liquid 13 from a reservoir 14 through a filter 15. As used herein, “high flash point liquid” refers to a material that is a liquid under atmospheric pressure and room temperatures and becomes flammable when it is subjected to “high temperatures”, such as temperatures greater than 100 degrees Fahrenheit. A check valve 16 is included to selectively isolate pump 12 and reservoir 14 from the remainder of pumping system 10. In this regard, a bypass hose 18 is included that may be opened via a ball valve 20. Downstream from check valve 16 is a normally closed two-way solenoid valve 22 followed by a manifold 24 through which a high pressure switch 26 and a gauge 28 are connected. Further downstream, a plurality of ball valves 30, 32, 34 are arranged to isolate individual sections of pumping system 10. In particular, valve 30 may be utilized to isolate the previously-described section of pumping system 10 that includes pump 12 from an accumulator loop 36 and a burner head supply line 38. Additionally or alternatively, valves 32, 34 may be utilized to selectively isolate the previously-described section of pumping system 10 including motor 12 from one of accumulator loop 36 or burner head supply line 38.

Accumulator loop 36 includes an accumulator 40, preferably in the form of a bladder accumulator, that may be isolated from a remainder of accumulator loop 36 via valve 34. Downstream of accumulator 40 and valve 34 are a normally open two-way relief solenoid valve 42 and a gauge 44 designed to relieve pressure in the accumulator loop 36 as the high flash point liquid 13 collected in accumulator 40 is delivered back to reservoir 14. Additionally, all pressure in burner head supply line 38 will be relieved upon removing power to the relief valve 42.

Referring now to burner head supply line 38, a regulator 46 is included having a 4,000 pound per square inch (psi) maximum pressure inlet and a pressure gauge 48 designed to indicate the pressure at regulator 46. Downstream of regulator 46 is a low pressure switch 50. As will be described in detail below, a control panel 52 is included to control pumping system 50.

Referring now to FIG. 2, a burner system 54 is shown that is also controlled by control panel 52 and designed to receive the high flash point liquid 13 pumped from pumping system 10 of FIG. 1. Burner system 54 includes a plurality of burner heads 56, 58, 60. It should be noted that, in order to simplify the description of burner system 54, only three burner heads 56, 58, 60 are shown. However, it is contemplated that a large array of burner heads, for example, ten or more, may be included in burner system 54.

An additional accumulator 61 may be included that along with the high flash point liquid 13 delivered via burner head supply line 38, delivers high flash point liquid 13 through a filter 62 and ball valve 64 associated with each burner head 56, 58, 60. A normally closed solenoid valve 66 is arranged as a last barrier to the high flash point liquid 13 before passing beside housing 68 of the burner heads 56, 58, 60. Along side each burner head housing 68, a nozzle 70 is arranged within an expelling port 72 so as to align an orifice 74 of nozzle 70 with an igniter 76 that is also disposed with expelling port 72. Igniter 76 includes a pair of electrodes 78 arranged in a configuration commonly found in spark plug systems such as utilized in automobiles and the like. Also, an optical sensor 80 and relay 82 that form an ignition verification sensor 83 are at least partially arranged within each burner head housing 68. Accordingly, as will be described, ignition verification sensor 83 communicates an ignition confirmation signal back to control panel 52 before control panel 52 opens valve 66.

Referring now to FIGS. 1 and 2, in operation, pumping system 10 and burner system 54 are controlled via control panel 52. It should be noted that control panel 52 may include multiple interfaces for independently controlling and operating the components of pumping system 10 and burner system 54. Also, control panel 52 may be specifically designed to control pumping system 10 and burner system 54 alone or may be part of a larger effects system to control lights, sounds, and the like.

In either case, when initiated via control panel 52, pump 12 draws the high flash point liquid 13 from reservoir 14 through filter 15. According to one embodiment, the high flash point liquid 13 is designed to remain in the liquid state under normal atmospheric pressures and at normal operating temperatures. Hence, the high flash point liquid 13 is drawn from reservoir 14 and is pumped under pressure toward check valve 16. It is contemplated that check valve 16 may be designed to operate under pressures between 0 psi and 3,000 psi as pumping system 10 is designed to pump the high flash point liquid 13 under pressures of, preferably, approximately 500 psi, but up to pressures in excess of 1,500 psi. Should bypass valve 20 be tripped, the high flash point liquid 13 drawn by pump 12 will be permitted to flow past bypass valve 20 through bypass hose 18 and back into reservoir 14.

Under normal operating conditions, high flash point liquid 13 will pass through check valve 16 toward normally closed two-way solenoid valve 22. In this regard, normally closed two-way solenoid valve 22 may be controlled via control panel 52 to halt the flow of the high flash point liquid 13 from reservoir 14. Accordingly, as will be described, normally closed two-way solenoid valve 22 serves as one of numerous isolation valves for both pumping system 10 and burner system 54.

Under normal operating conditions, normally closed two-way solenoid valve 22 will permit high flash point liquid 13 to continue to manifold 24. Associated with manifold 24 is high pressure switch 26 and gauge 28 that is designed to indicate the pressure sensed by high pressure switch 26. High pressure switch 26, according to one embodiment, is designed to have a normal operating range of approximately 180 psi to 3000 psi. Accordingly, gauge 28, according to one embodiment, has an operating range of 0 psi to 3,000 psi with 50 psi increments indicated thereon. Therefore, should operating conditions reach an excess of 2000 psi, via gauge 28, high pressure switch 26 will indicate an excessive operating pressure and high pressure switch 26 will provide a signal to control panel 52 that, in turn, provides an alarm to the user by way of, for example, an audible or light-based alarm signal. Substantially simultaneously therewith, normally closed two-way solenoid valve 22 will be automatically closed and normally open two-way solenoid relief valve 42 will open in order to remedy the excessive operating pressure via accumulator loop 36 back to the reservoir 14.

Generally, excessive operating pressures will not occur, and high flash point liquid 13 will pass through manifold 24 and ball valve 30 where it will be stored in accumulator 40. Accumulator 40, for example a ten gallon bladder accumulator, is designed to receive excess high flash point liquid 13 that, as will be described, may not be consumed during the generation of effects flames. This excess high flash point liquid 13 can then be utilized in subsequent firings.

Ball Valve 34 shall always be opened during operation whereby high flash point liquid 13 can pass through normally open two-way solenoid relief valve 42 into accumulator relief loop 36 back to reservoir 14 when necessary. For example, it may be desirable to allow the high flash point liquid 13 to pass through normally open two-way solenoid relief valve 42 into accumulator relief loop 36 back to reservoir 14 when an over pressurization is indicated by high pressure switch 26 or in the case of an emergency shut-off situation indicated at control panel 52. By reading gauge 44, the operator can determine when all pressure has been removed from the system.

However, under normal flame effects generating operation, ball valve 34 will remain open and normally open two-way solenoid relief valve 42 will remain energized, closing off accumulator relief loop 36 in favor of ball valve 32. Accordingly, high flash point liquid 13 will flow along burner head supply line 38 and through regulator 46. According to one embodiment, regulator 46 has an operating range of approximately 0 psi to 2,000 psi with a max inlet psi of 4,000. After passing regulator 46, high flash point liquid 13 is monitored by low pressure switch 50. According to one embodiment, low pressure switch 50 has an operating range of approximately 30 psi to 600 psi. Accordingly, should the pressure along the burner supply line 38 drop below a desirable pressure, as determined by the low pressure switch 50, control panel 52 will remove the power supplied to all of the burner heads 56, 58, 60 until the low pressure condition can be remedied.

Under normal operating conditions, high flash point liquid 13 will continue to flow along burner supply path 38 and into burner system 54 of FIG. 2 where it will be additionally accumulated within accumulator 61. According to one embodiment, accumulator 61 is a five gallon bladder accumulator designed to collect additional high flash point liquid 13 in order to maintain a higher volume of high flash point liquid 13. High flash point liquid 13 pumped by pumping system 10 into accumulator 40 and 61 is passed through a filter 62 on its way to each burner head 56, 58, 60. As previously described, following each filter 62 is a ball valve 64 that allows each burner head 56, 58, 60 to be independently isolated by manually actuating ball valve 64. However, if manual actuation is not desired or in order to operate the burner system according to a preset or predefined sequence of firings, normally closed two-way solenoid valve 66 is controlled by control panel 52 to permit or prohibit the flow of high flash point liquid 13 pumped toward expelling port 72. It is contemplated that the control panel 52 may be located remotely from the other components of the system. Furthermore, it is contemplated that the control panel may be part of a DMX control console, or the like. The ability to pump high flash point liquid 13 under sustainable conditions for significant periods of time while being independently supplied to various burner heads 56, 58, 60 within the burner system 54 allows for numerous, for example, hundreds, of independently initiated and coordinated flames or explosions to be expelled through the expelling ports 72.

According to one embodiment, normally closed two-way solenoid valve 66 is designed to have an operating pressure of approximately 1,100 psi such that the high flash point liquid 13 enters nozzle 70 under substantial pressure. In this regard, high flash point liquid 13 is forced through orifice 74 at such a rate and pressure that it is either atomized or vaporized. Accordingly, it is contemplated that high flash point liquid 13 when either atomized or vaporized enters a volatile state such that it will be ignitable when exposed to a spark generated by igniter 76.

In this regard, according to one embodiment, high flash point liquid 13 is a material commercially available as Isopar. Isopar is a registered trademark owned by Exxon Mobile Corporation of Texas. Specifically, high flash point liquid 13 may be Isopar type M and, preferably, may be Isopar type G. By utilizing Isopar G, high flash point liquid 13 may be forced through a nozzle 70 at pressures of approximately 500 psi and still sufficiently atomize or vaporize so as to enter a volatile state to be, preferably, completely consumed by the explosion resulting from exposure to a spark formed between electrodes 78 of burner 76.

In order to achieve substantially complete consumption of high flash point liquid 13 under pressures as low as 500 psi, it is contemplated that orifice 74 may be sized from approximately 1/16 of an inch to 1/32 of an inch. In this regard, it is contemplated that since, as will be described, each burner head 56, 58, 60 can be independently supplied with high flash point liquid 13, varying orifice sizes may be utilized across burner system 54 to generate various flame or explosion sizes and heights, for example, from between a few feet to tens of feet. To provide further flexibility, it is contemplated that nozzle 70 may be an interchangeable nozzle such that varying orifices may be presented throughout burner system 54.

As a further check against undesired operating conditions, prior to normally closed two-way solenoid valve 66 allowing high flash point liquid 13 to enter an associated burner head 56, 58, 60, the igniter 76 is caused to generate a spark that can be detected by optical sensor 80 to verify that, when atomized or vaporized high flash point liquid 13 is expelled through orifice 74 of nozzle 70, it will be properly ignited. That is, optical sensor 80 is arranged to monitor the gap between electrodes 78 of the burner 76, and upon sensing an ultra violet light increase within the expelling ports 72 indicative of an ignition spark, sends a signal to relay 82. Relay 82 in turn, sends an ignition confirmation signal to control panel 52. As such, burner system 54 is controlled via control panel 52 to preclude high flash point liquid 13 from even entering a burner head 56, 58, 60 when igniter 76 has not been energized or has failed to produce a spark. Accordingly, burner system 54 is highly modular such that a supply of high flash point liquid 13 to any of the burner heads 56, 58, 60 can be independently controlled, maintained, and operated, according to preset safety protocol, predesigned display patterns, and/or manually actuated firing sequences. In this regard, it is contemplated that control panel 52 may control normally closed two-way solenoid valve 66 according to a DMX-512 protocol. In particular, a remotely located DMX control console including control panel 52 controls normally closed two-way solenoid valve 66 to open using a DMX-512 protocol signal only after optical sensor 80 and relay 82 have provided a positive indication or confirmation that a spark has been generated between electrodes 78 of burner 76.

It is contemplated that the pumping system 10 and burner system 54 may be incorporated into a permanent or semi-permanent installation, such as a stage for live acting or an amusement ride. Furthermore, it is contemplated that the pumping system 10 and burner system 54 may be arranged in a mobile installation to be readily transported. In this regard, the pumping system 10 and burner system 54 may be utilized in touring arrangements, such as touring stage shows.

Therefore, a system and method for generating flame effects is created utilizing a pumping system and burning system having a plurality of valve points configured to feed a material that is combustible when atomized or vaporized to an array of independently controllable burners. In accordance with one embodiment, the material is Isopar G, which can be sufficiently atomized or vaporized to substantially prevent fallout (i.e. liquid not completely consumed by the combustion of the high flash point fluid 13) by passing it through an orifice of approximately 1/16 of an inch at pressures as low as 500 psi.

A controller is provided that controls the elements of the pumping system and burner system according to preset safety protocol. A control console is provided that has been programmed with predetermined firing patterns, and/or manually actuated firing patterns. To this end, a sensor system is arranged to confirm proper ignition of an igniter in each burner prior to the controller allowing any atomized or vaporized material to be ejected from the system. As such, a sustainable pattern of firings mapped to a desired sequence is achievable under conditions compliant with various safety standards such as National Fire Protection Act 160. To further control operation of the system, a variety of additional valves and switches may be included. In this regard, the system may automatically isolate portions of the flow path upon detection of low or high pressure conditions.

The present invention has been described in terms of the preferred embodiment, and it should be appreciated that many equivalents, alternatives, variations, and modifications, aside from those expressly stated, are possible and within the scope of the invention. Therefore, the invention should not be limited to a particular described embodiment. 

1. A system for generating flame effects comprising: an array of burner heads, each having an igniter configured to generate an ignition spark; a reservoir containing a high flash point liquid; a pump configured to draw the high flash point liquid from the reservoir and pump it under high pressure to the array of burner heads; a solenoid valve arranged at each burner in the array of burner heads to control a flow of the high flash point liquid through each burner head; a nozzle arranged at each burner head to convert the high flash point liquid to a combustible form; a sensor arranged at each burner head to generate an ignition confirmation signal upon detecting the ignition spark at the igniter; and a controller programmed to independently control each valve to control the flow of the high flash point liquid to the burner based on the ignition confirmation signal.
 2. The system of claim 1 wherein the controller is further configured to only allow the flow of the high flash point liquid to the burner when an ignition confirmation signal has been received from the sensor monitoring the burner.
 3. The system of claim 1 wherein the controller is further configured to control each valve according to a predetermined pattern and only open a valve arranged at a particular burner head if the sensor monitoring the burner of the particular burner head is generating the ignition confirmation signal by sending a DMX-512 protocol signal to open the valve.
 4. The system of claim 1 wherein the burner includes a spark plug and wherein the sensor includes an optical sensor coupled to a relay configured to generate the ignition confirmation signal in response to a signal from the optical sensor indicating a spark generated by the spark plug.
 5. The system of claim 1 wherein the high flash point liquid includes Isopar G.
 6. The system of claim 1 further comprising at least one of a low pressure switch and a high pressure switch configured to at least one of remove power supplied to the burner heads and close a shut-off valve and open a relief valve simultaneously upon detecting an undesirable pressure condition between the reservoir and the array of burner heads.
 7. The system of claim 1 further comprising a flame safeguard control module configured to prohibit the flow of the high flash point liquid to the burner unless the ignition confirmation signal is received from the sensor monitoring the burner.
 8. The system of claim 1 further comprising at least one accumulator and wherein at least one accumulator and the reservoir include a flexible bladder.
 9. The system of claim 1 wherein the pump is configured to pump the high flash point liquid under a pressure of greater than 500 pounds per square inch (psi).
 10. The system of claim 1 wherein the array of burner heads includes at least ten independently controllable burner heads.
 11. A system for generating flame effects comprising: a reservoir having a material stored therein having a high flash point in a liquid state and combustible when atomized; a pump configured to move the material from the reservoir toward an expelling port; at least one burner head disposed at the expelling port comprising: a nozzle configured to receive the material and at least one of atomize and vaporize the material; a valve configured to restrict the material from passing through the nozzle; an igniter configured to ignite the material as it passes from the nozzle to generate the flame effects; a sensor configured to monitor the igniter to determine proper ignition of the burner; and a controller configured to control the valve to restrict the material from passing from the nozzle if the sensor has not determined ignition of the burner.
 12. The system of claim 11 further comprising an array of burner heads disposed at respective expelling ports and having respective valves configured to restrict the material from passing from respective nozzles, and wherein the controller is further configured to independently control the valves of each burner head in the array of burner heads; to restrict the material from passing from any nozzle where a respective sensor has not determined ignition of the burner.
 13. The system of claim 11 wherein the sensor includes at least one optical sensor configured to detect a luminescence increase indicative of burner ignition and relay configured to send an ignition confirmation signal to the controller indicating that the optical sensor has detected burner ignition.
 14. The system of claim 13 wherein the burner includes a spark plug, and wherein the optical sensor is configured to detect a luminescence increase within the expelling port caused by a spark generated by the spark plug.
 15. The system of claim 11 further comprising a passage extending between the reservoir and the expelling port and at least one low pressure switch coupled to at least one valve disposed between the pump and the nozzle to restrict movement of the material from the reservoir to the expelling port upon detecting a low pressure condition in the passage and at least one high pressure switch coupled to at least one valve disposed between the pump and the nozzle to restrict movement of the material from the reservoir to the expelling port upon detecting a high pressure condition in the passage.
 16. The system of claim 11 further comprising a plurality of isolation valves including at least one valve disposed proximate to the reservoir to restrict the material from passing therefrom.
 17. The system of claim 11 where in the material includes Isopar.
 18. The system of claim 11 wherein the pump is configured to push the material from the nozzle at a pressure of greater than 500 psi.
 19. The system of claim 11 wherein the sensor is configured to detect ultraviolet light to determine proper ignition of the burner.
 20. A method for generating flame effects comprising: pumping a high flash point liquid from a reservoir toward a plurality of nozzles configured to atomize the high flash point liquid before being passed by an igniter; sparking an igniter associated with each of the plurality of nozzles according to a predetermined pattern to ignite the atomized high flash point liquid and generate the flame effects; monitoring each igniter to confirm sparking of each igniter before expelling the atomized high flash point liquid according to the predetermined pattern; and independently controlling valves located at each of the plurality of nozzles to only open a valve after sparking of the igniter has been confirmed.
 21. The method of claim 20 further comprising controlling the valves to generate the flame effects in compliance with a National Fire Protection Act (NFPA) 160 standard. 